/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2019 Ha Thach (tinyusb.org)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * This file is part of the TinyUSB stack.
 */

#include "tusb_option.h"

#if CFG_TUD_ENABLED

#include "device/dcd.h"
#include "tusb.h"
#include "common/tusb_private.h"

#include "device/usbd.h"
#include "device/usbd_pvt.h"

//--------------------------------------------------------------------+
// USBD Configuration
//--------------------------------------------------------------------+

// Debug level of USBD
#define USBD_DBG 2

#ifndef CFG_TUD_TASK_QUEUE_SZ
#define CFG_TUD_TASK_QUEUE_SZ 16
#endif

//--------------------------------------------------------------------+
// Device Data
//--------------------------------------------------------------------+

// Invalid driver ID in itf2drv[] ep2drv[][] mapping
enum { DRVID_INVALID = 0xFFu };

typedef struct
{
    struct TU_ATTR_PACKED {
        volatile uint8_t connected : 1;
        volatile uint8_t addressed : 1;
        volatile uint8_t suspended : 1;

        uint8_t remote_wakeup_en : 1; // enable/disable by host
        uint8_t remote_wakeup_support : 1; // configuration descriptor's attribute
        uint8_t self_powered : 1; // configuration descriptor's attribute
    };

    volatile uint8_t cfg_num; // current active configuration (0x00 is not configured)
    uint8_t speed;

    uint8_t itf2drv[CFG_TUD_INTERFACE_MAX]; // map interface number to driver (0xff is invalid)
    uint8_t ep2drv[CFG_TUD_ENDPPOINT_MAX][2]; // map endpoint to driver ( 0xff is invalid ), can use only 4-bit each

    tu_edpt_state_t ep_status[CFG_TUD_ENDPPOINT_MAX][2];

} usbd_device_t;

static usbd_device_t _usbd_dev;

//--------------------------------------------------------------------+
// Class Driver
//--------------------------------------------------------------------+
#if CFG_TUSB_DEBUG >= 2
#define DRIVER_NAME(_name) .name = _name,
#else
#define DRIVER_NAME(_name)
#endif

// 编译内建的USB驱动
static usbd_class_driver_t const _usbd_driver[] = {
#if CFG_TUD_CDC
    { DRIVER_NAME("CDC")
            .init
        = cdcd_init,
        .reset = cdcd_reset,
        .open = cdcd_open,
        .control_xfer_cb = cdcd_control_xfer_cb,
        .xfer_cb = cdcd_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_MSC
    { DRIVER_NAME("MSC")
            .init
        = mscd_init,
        .reset = mscd_reset,
        .open = mscd_open,
        .control_xfer_cb = mscd_control_xfer_cb,
        .xfer_cb = mscd_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_HID
    { DRIVER_NAME("HID")
            .init
        = hidd_init,
        .reset = hidd_reset,
        .open = hidd_open,
        .control_xfer_cb = hidd_control_xfer_cb,
        .xfer_cb = hidd_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_AUDIO
    { DRIVER_NAME("AUDIO")
            .init
        = audiod_init,
        .reset = audiod_reset,
        .open = audiod_open,
        .control_xfer_cb = audiod_control_xfer_cb,
        .xfer_cb = audiod_xfer_cb,
        .sof = audiod_sof_isr },
#endif

#if CFG_TUD_VIDEO
    { DRIVER_NAME("VIDEO")
            .init
        = videod_init,
        .reset = videod_reset,
        .open = videod_open,
        .control_xfer_cb = videod_control_xfer_cb,
        .xfer_cb = videod_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_MIDI
    { DRIVER_NAME("MIDI")
            .init
        = midid_init,
        .open = midid_open,
        .reset = midid_reset,
        .control_xfer_cb = midid_control_xfer_cb,
        .xfer_cb = midid_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_VENDOR
    { DRIVER_NAME("VENDOR")
            .init
        = vendord_init,
        .reset = vendord_reset,
        .open = vendord_open,
        .control_xfer_cb = tud_vendor_control_xfer_cb,
        .xfer_cb = vendord_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_USBTMC
    { DRIVER_NAME("TMC")
            .init
        = usbtmcd_init_cb,
        .reset = usbtmcd_reset_cb,
        .open = usbtmcd_open_cb,
        .control_xfer_cb = usbtmcd_control_xfer_cb,
        .xfer_cb = usbtmcd_xfer_cb,
        .sof = NULL },
#endif

#if CFG_TUD_DFU_RUNTIME
    { DRIVER_NAME("DFU-RUNTIME")
            .init
        = dfu_rtd_init,
        .reset = dfu_rtd_reset,
        .open = dfu_rtd_open,
        .control_xfer_cb = dfu_rtd_control_xfer_cb,
        .xfer_cb = NULL,
        .sof = NULL },
#endif

#if CFG_TUD_DFU
    { DRIVER_NAME("DFU")
            .init
        = dfu_moded_init,
        .reset = dfu_moded_reset,
        .open = dfu_moded_open,
        .control_xfer_cb = dfu_moded_control_xfer_cb,
        .xfer_cb = NULL,
        .sof = NULL },
#endif

#if CFG_TUD_ECM_RNDIS || CFG_TUD_NCM
    {
        DRIVER_NAME("NET")
            .init
        = netd_init,
        .reset = netd_reset,
        .open = netd_open,
        .control_xfer_cb = netd_control_xfer_cb,
        .xfer_cb = netd_xfer_cb,
        .sof = NULL,
    },
#endif

#if CFG_TUD_BTH
    { DRIVER_NAME("BTH")
            .init
        = btd_init,
        .reset = btd_reset,
        .open = btd_open,
        .control_xfer_cb = btd_control_xfer_cb,
        .xfer_cb = btd_xfer_cb,
        .sof = NULL },
#endif
};

enum { BUILTIN_DRIVER_COUNT = TU_ARRAY_SIZE(_usbd_driver) };

// Additional class drivers implemented by application
static usbd_class_driver_t const* _app_driver = NULL;
static uint8_t _app_driver_count = 0; // 用户驱动个数

/**
 * @brief 获取驱动
 *
 * @param drvid 驱动序号
 * @return usbd_class_driver_t const*
 */
static inline usbd_class_driver_t const* get_driver(uint8_t drvid)
{
    // 用户自己添加驱动
    if (usbd_app_driver_get_cb) {
        if (drvid < _app_driver_count)
            return &_app_driver[drvid];
        drvid -= _app_driver_count;
    }

    // 内建的驱动
    if (drvid < BUILTIN_DRIVER_COUNT)
        return &_usbd_driver[drvid];

    return NULL;
}

// 总共驱动个数(用户驱动 + 内建驱动)
#define TOTAL_DRIVER_COUNT (_app_driver_count + BUILTIN_DRIVER_COUNT)

//--------------------------------------------------------------------+
// DCD Event
//--------------------------------------------------------------------+

enum { RHPORT_INVALID = 0xFFu };
static uint8_t _usbd_rhport = RHPORT_INVALID;

// Event queue
// usbd_int_set() is used as mutex in OS NONE config
OSAL_QUEUE_DEF(usbd_int_set, _usbd_qdef, CFG_TUD_TASK_QUEUE_SZ, dcd_event_t);
static osal_queue_t _usbd_q;

// Mutex for claiming endpoint, only needed when using with preempted RTOS
#if CFG_TUSB_OS != OPT_OS_NONE
static osal_mutex_def_t _ubsd_mutexdef;
static osal_mutex_t _usbd_mutex;
#endif

//--------------------------------------------------------------------+
// Prototypes
//--------------------------------------------------------------------+
static bool process_control_request(uint8_t rhport, tusb_control_request_t const* p_request);
static bool process_set_config(uint8_t rhport, uint8_t cfg_num);
static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const* p_request);

// from usbd_control.c
void usbd_control_reset(void);
void usbd_control_set_request(tusb_control_request_t const* request);
void usbd_control_set_complete_callback(usbd_control_xfer_cb_t fp);
bool usbd_control_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes);

//--------------------------------------------------------------------+
// Debug
//--------------------------------------------------------------------+
#if CFG_TUSB_DEBUG >= 2
static char const* const _usbd_event_str[DCD_EVENT_COUNT] = {
    "Invalid",
    "Bus Reset",
    "Unplugged",
    "SOF",
    "Suspend",
    "Resume",
    "Setup Received",
    "Xfer Complete",
    "Func Call"
};

// for usbd_control to print the name of control complete driver
void usbd_driver_print_control_complete_name(usbd_control_xfer_cb_t callback)
{
    for (uint8_t i = 0; i < TOTAL_DRIVER_COUNT; i++) {
        usbd_class_driver_t const* driver = get_driver(i);
        if (driver && driver->control_xfer_cb == callback) {
            TU_LOG(USBD_DBG, "  %s control complete\r\n", driver->name);
            return;
        }
    }
}
#endif // CFG_TUSB_DEBUG >= 2

//--------------------------------------------------------------------+
// Application API
//--------------------------------------------------------------------+
tusb_speed_t tud_speed_get(void)
{
    return (tusb_speed_t)_usbd_dev.speed;
}

bool tud_connected(void)
{
    return _usbd_dev.connected;
}

bool tud_mounted(void)
{
    return _usbd_dev.cfg_num ? true : false;
}

bool tud_suspended(void)
{
    return _usbd_dev.suspended;
}

bool tud_remote_wakeup(void)
{
    // only wake up host if this feature is supported and enabled and we are suspended
    TU_VERIFY(_usbd_dev.suspended && _usbd_dev.remote_wakeup_support && _usbd_dev.remote_wakeup_en);
    dcd_remote_wakeup(_usbd_rhport);
    return true;
}

bool tud_disconnect(void)
{
    TU_VERIFY(dcd_disconnect);
    dcd_disconnect(_usbd_rhport);
    return true;
}

bool tud_connect(void)
{
    TU_VERIFY(dcd_connect);
    dcd_connect(_usbd_rhport);
    return true;
}

//--------------------------------------------------------------------+
// USBD Task
//--------------------------------------------------------------------+
bool tud_inited(void)
{
    return _usbd_rhport != RHPORT_INVALID;
}

bool tud_init(uint8_t rhport)
{
    // skip if already initialized
    if (tud_inited())
        return true;

    TU_LOG(USBD_DBG, "USBD init on controller %u\r\n", rhport);
    TU_LOG_INT(USBD_DBG, sizeof(usbd_device_t));

    tu_varclr(&_usbd_dev);

#if CFG_TUSB_OS != OPT_OS_NONE
    // Init device mutex
    _usbd_mutex = osal_mutex_create(&_ubsd_mutexdef);
    TU_ASSERT(_usbd_mutex);
#endif

    // Init device queue & task
    _usbd_q = osal_queue_create(&_usbd_qdef);
    TU_ASSERT(_usbd_q);

    // 获取用户驱动程序（如果可用）
    if (usbd_app_driver_get_cb) {
        _app_driver = usbd_app_driver_get_cb(&_app_driver_count);
    }

    // 初始化驱动程序
    for (uint8_t i = 0; i < TOTAL_DRIVER_COUNT; i++) {
        usbd_class_driver_t const* driver = get_driver(i);
        TU_ASSERT(driver);
        TU_LOG(USBD_DBG, "%s init\r\n", driver->name);
        driver->init();
    }

    _usbd_rhport = rhport;

    // Init device controller driver
    dcd_init(rhport);
    dcd_int_enable(rhport);

    return true;
}

/**
 * @brief 复位驱动程序
 *
 * @param rhport
 */
static void configuration_reset(uint8_t rhport)
{
    for (uint8_t i = 0; i < TOTAL_DRIVER_COUNT; i++) {
        usbd_class_driver_t const* driver = get_driver(i);
        TU_ASSERT(driver, );
        driver->reset(rhport);
    }

    tu_varclr(&_usbd_dev);
    memset(_usbd_dev.itf2drv, DRVID_INVALID, sizeof(_usbd_dev.itf2drv)); // invalid mapping
    memset(_usbd_dev.ep2drv, DRVID_INVALID, sizeof(_usbd_dev.ep2drv)); // invalid mapping
}

static void usbd_reset(uint8_t rhport)
{
    configuration_reset(rhport);
    usbd_control_reset();
}

bool tud_task_event_ready(void)
{
    // Skip if stack is not initialized
    if (!tusb_inited())
        return false;

    return !osal_queue_empty(_usbd_q);
}

/* USB Device Driver task
 * This top level thread manages all device controller event and delegates events to class-specific drivers.
 * This should be called periodically within the mainloop or rtos thread.
 *
   @code
    int main(void)
    {
      application_init();
      tusb_init();

      while(1) // the mainloop
      {
        application_code();
        tud_task(); // tinyusb device task
      }
    }
    @endcode
 */
void tud_task_ext(uint32_t timeout_ms, bool in_isr)
{
    (void)in_isr; // not implemented yet

    // Skip if stack is not initialized
    if (!tusb_inited())
        return;

    // Loop until there is no more events in the queue
    while (1) {
        dcd_event_t event;
        if (!osal_queue_receive(_usbd_q, &event, timeout_ms))
            return;

#if CFG_TUSB_DEBUG >= 2
        if (event.event_id == DCD_EVENT_SETUP_RECEIVED)
            TU_LOG(USBD_DBG, "\r\n"); // extra line for setup
        TU_LOG(USBD_DBG, "USBD %s ", event.event_id < DCD_EVENT_COUNT ? _usbd_event_str[event.event_id] : "CORRUPTED");
#endif

        switch (event.event_id) {
        case DCD_EVENT_BUS_RESET:
            TU_LOG(USBD_DBG, ": %s Speed\r\n", tu_str_speed[event.bus_reset.speed]);
            usbd_reset(event.rhport);
            _usbd_dev.speed = event.bus_reset.speed;
            break;

        case DCD_EVENT_UNPLUGGED:
            TU_LOG(USBD_DBG, "\r\n");
            usbd_reset(event.rhport);

            // invoke callback
            if (tud_umount_cb)
                tud_umount_cb();
            break;

        case DCD_EVENT_SETUP_RECEIVED:
            TU_LOG_VAR(USBD_DBG, &event.setup_received);
            TU_LOG(USBD_DBG, "\r\n");

            // Mark as connected after receiving 1st setup packet.
            // But it is easier to set it every time instead of wasting time to check then set
            _usbd_dev.connected = 1;

            // mark both in & out control as free
            _usbd_dev.ep_status[0][TUSB_DIR_OUT].busy = false;
            _usbd_dev.ep_status[0][TUSB_DIR_OUT].claimed = 0;
            _usbd_dev.ep_status[0][TUSB_DIR_IN].busy = false;
            _usbd_dev.ep_status[0][TUSB_DIR_IN].claimed = 0;

            // Process control request
            if (!process_control_request(event.rhport, &event.setup_received)) {
                TU_LOG(USBD_DBG, "  Stall EP0\r\n");
                // Failed -> stall both control endpoint IN and OUT
                dcd_edpt_stall(event.rhport, 0);
                dcd_edpt_stall(event.rhport, 0 | TUSB_DIR_IN_MASK);
            }
            break;

        case DCD_EVENT_XFER_COMPLETE: {
            // Invoke the class callback associated with the endpoint address
            uint8_t const ep_addr = event.xfer_complete.ep_addr;
            uint8_t const epnum = tu_edpt_number(ep_addr);
            uint8_t const ep_dir = tu_edpt_dir(ep_addr);

            TU_LOG(USBD_DBG, "on EP %02X with %u bytes\r\n", ep_addr, (unsigned int)event.xfer_complete.len);

            _usbd_dev.ep_status[epnum][ep_dir].busy = false;
            _usbd_dev.ep_status[epnum][ep_dir].claimed = 0;

            if (0 == epnum) {
                usbd_control_xfer_cb(event.rhport, ep_addr, (xfer_result_t)event.xfer_complete.result, event.xfer_complete.len);
            } else {
                usbd_class_driver_t const* driver = get_driver(_usbd_dev.ep2drv[epnum][ep_dir]);
                TU_ASSERT(driver, );

                TU_LOG(USBD_DBG, "  %s xfer callback\r\n", driver->name);
                driver->xfer_cb(event.rhport, ep_addr, (xfer_result_t)event.xfer_complete.result, event.xfer_complete.len);
            }
        } break;

        case DCD_EVENT_SUSPEND:
            // NOTE: When plugging/unplugging device, the D+/D- state are unstable and
            // can accidentally meet the SUSPEND condition ( Bus Idle for 3ms ), which result in a series of event
            // e.g suspend -> resume -> unplug/plug. Skip suspend/resume if not connected
            if (_usbd_dev.connected) {
                TU_LOG(USBD_DBG, ": Remote Wakeup = %u\r\n", _usbd_dev.remote_wakeup_en);
                if (tud_suspend_cb)
                    tud_suspend_cb(_usbd_dev.remote_wakeup_en);
            } else {
                TU_LOG(USBD_DBG, " Skipped\r\n");
            }
            break;

        case DCD_EVENT_RESUME:
            if (_usbd_dev.connected) {
                TU_LOG(USBD_DBG, "\r\n");
                if (tud_resume_cb)
                    tud_resume_cb();
            } else {
                TU_LOG(USBD_DBG, " Skipped\r\n");
            }
            break;

        case USBD_EVENT_FUNC_CALL:
            TU_LOG(USBD_DBG, "\r\n");
            if (event.func_call.func)
                event.func_call.func(event.func_call.param);
            break;

        case DCD_EVENT_SOF:
        default:
            TU_BREAKPOINT();
            break;
        }

#if CFG_TUSB_OS != OPT_OS_NONE && CFG_TUSB_OS != OPT_OS_PICO
        // return if there is no more events, for application to run other background
        if (osal_queue_empty(_usbd_q))
            return;
#endif
    }
}

//--------------------------------------------------------------------+
// Control Request Parser & Handling
//--------------------------------------------------------------------+

// Helper to invoke class driver control request handler
static bool invoke_class_control(uint8_t rhport, usbd_class_driver_t const* driver, tusb_control_request_t const* request)
{
    usbd_control_set_complete_callback(driver->control_xfer_cb);
    TU_LOG(USBD_DBG, "  %s control request\r\n", driver->name);
    return driver->control_xfer_cb(rhport, CONTROL_STAGE_SETUP, request);
}

// This handles the actual request and its response.
// return false will cause its caller to stall control endpoint
static bool process_control_request(uint8_t rhport, tusb_control_request_t const* p_request)
{
    usbd_control_set_complete_callback(NULL);

    TU_ASSERT(p_request->bmRequestType_bit.type < TUSB_REQ_TYPE_INVALID);

    // Vendor request
    if (p_request->bmRequestType_bit.type == TUSB_REQ_TYPE_VENDOR) {
        TU_VERIFY(tud_vendor_control_xfer_cb);

        usbd_control_set_complete_callback(tud_vendor_control_xfer_cb);
        return tud_vendor_control_xfer_cb(rhport, CONTROL_STAGE_SETUP, p_request);
    }

#if CFG_TUSB_DEBUG >= 2
    if (TUSB_REQ_TYPE_STANDARD == p_request->bmRequestType_bit.type && p_request->bRequest <= TUSB_REQ_SYNCH_FRAME) {
        TU_LOG(USBD_DBG, "  %s", tu_str_std_request[p_request->bRequest]);
        if (TUSB_REQ_GET_DESCRIPTOR != p_request->bRequest)
            TU_LOG(USBD_DBG, "\r\n");
    }
#endif

    switch (p_request->bmRequestType_bit.recipient) {
    //------------- Device Requests e.g in enumeration -------------//
    case TUSB_REQ_RCPT_DEVICE:
        if (TUSB_REQ_TYPE_CLASS == p_request->bmRequestType_bit.type) {
            uint8_t const itf = tu_u16_low(p_request->wIndex);
            TU_VERIFY(itf < TU_ARRAY_SIZE(_usbd_dev.itf2drv));

            usbd_class_driver_t const* driver = get_driver(_usbd_dev.itf2drv[itf]);
            TU_VERIFY(driver);

            // forward to class driver: "non-STD request to Interface"
            return invoke_class_control(rhport, driver, p_request);
        }

        if (TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type) {
            // Non standard request is not supported
            TU_BREAKPOINT();
            return false;
        }

        switch (p_request->bRequest) {
        case TUSB_REQ_SET_ADDRESS:
            // Depending on mcu, status phase could be sent either before or after changing device address,
            // or even require stack to not response with status at all
            // Therefore DCD must take full responsibility to response and include zlp status packet if needed.
            usbd_control_set_request(p_request); // set request since DCD has no access to tud_control_status() API
            dcd_set_address(rhport, (uint8_t)p_request->wValue);
            // skip tud_control_status()
            _usbd_dev.addressed = 1;
            break;

        case TUSB_REQ_GET_CONFIGURATION: {
            uint8_t cfg_num = _usbd_dev.cfg_num;
            tud_control_xfer(rhport, p_request, &cfg_num, 1);
        } break;

        case TUSB_REQ_SET_CONFIGURATION: {
            uint8_t const cfg_num = (uint8_t)p_request->wValue;

            // Only process if new configure is different
            if (_usbd_dev.cfg_num != cfg_num) {
                if (_usbd_dev.cfg_num) {
                    // already configured: need to clear all endpoints and driver first
                    TU_LOG(USBD_DBG, "  Clear current Configuration (%u) before switching\r\n", _usbd_dev.cfg_num);

                    // close all non-control endpoints, cancel all pending transfers if any
                    dcd_edpt_close_all(rhport);

                    // close all drivers and current configured state except bus speed
                    uint8_t const speed = _usbd_dev.speed;
                    configuration_reset(rhport);

                    _usbd_dev.speed = speed; // restore speed
                }

                // switch to new configuration if not zero
                if (cfg_num)
                    TU_ASSERT(process_set_config(rhport, cfg_num));
            }

            _usbd_dev.cfg_num = cfg_num;
            tud_control_status(rhport, p_request);
        } break;

        case TUSB_REQ_GET_DESCRIPTOR:
            TU_VERIFY(process_get_descriptor(rhport, p_request));
            break;

        case TUSB_REQ_SET_FEATURE:
            // Only support remote wakeup for device feature
            TU_VERIFY(TUSB_REQ_FEATURE_REMOTE_WAKEUP == p_request->wValue);

            TU_LOG(USBD_DBG, "    Enable Remote Wakeup\r\n");

            // Host may enable remote wake up before suspending especially HID device
            _usbd_dev.remote_wakeup_en = true;
            tud_control_status(rhport, p_request);
            break;

        case TUSB_REQ_CLEAR_FEATURE:
            // Only support remote wakeup for device feature
            TU_VERIFY(TUSB_REQ_FEATURE_REMOTE_WAKEUP == p_request->wValue);

            TU_LOG(USBD_DBG, "    Disable Remote Wakeup\r\n");

            // Host may disable remote wake up after resuming
            _usbd_dev.remote_wakeup_en = false;
            tud_control_status(rhport, p_request);
            break;

        case TUSB_REQ_GET_STATUS: {
            // Device status bit mask
            // - Bit 0: Self Powered
            // - Bit 1: Remote Wakeup enabled
            uint16_t status = (uint16_t)((_usbd_dev.self_powered ? 1u : 0u) | (_usbd_dev.remote_wakeup_en ? 2u : 0u));
            tud_control_xfer(rhport, p_request, &status, 2);
        } break;

        // Unknown/Unsupported request
        default:
            TU_BREAKPOINT();
            return false;
        }
        break;

    //------------- Class/Interface Specific Request -------------//
    case TUSB_REQ_RCPT_INTERFACE: {
        uint8_t const itf = tu_u16_low(p_request->wIndex);
        TU_VERIFY(itf < TU_ARRAY_SIZE(_usbd_dev.itf2drv));

        usbd_class_driver_t const* driver = get_driver(_usbd_dev.itf2drv[itf]);
        TU_VERIFY(driver);

        // all requests to Interface (STD or Class) is forwarded to class driver.
        // notable requests are: GET HID REPORT DESCRIPTOR, SET_INTERFACE, GET_INTERFACE
        if (!invoke_class_control(rhport, driver, p_request)) {
            // For GET_INTERFACE and SET_INTERFACE, it is mandatory to respond even if the class
            // driver doesn't use alternate settings or implement this
            TU_VERIFY(TUSB_REQ_TYPE_STANDARD == p_request->bmRequestType_bit.type);

            switch (p_request->bRequest) {
            case TUSB_REQ_GET_INTERFACE:
            case TUSB_REQ_SET_INTERFACE:
                // Clear complete callback if driver set since it can also stall the request.
                usbd_control_set_complete_callback(NULL);

                if (TUSB_REQ_GET_INTERFACE == p_request->bRequest) {
                    uint8_t alternate = 0;
                    tud_control_xfer(rhport, p_request, &alternate, 1);
                } else {
                    tud_control_status(rhport, p_request);
                }
                break;

            default:
                return false;
            }
        }
    } break;

    //------------- Endpoint Request -------------//
    case TUSB_REQ_RCPT_ENDPOINT: {
        uint8_t const ep_addr = tu_u16_low(p_request->wIndex);
        uint8_t const ep_num = tu_edpt_number(ep_addr);
        uint8_t const ep_dir = tu_edpt_dir(ep_addr);

        TU_ASSERT(ep_num < TU_ARRAY_SIZE(_usbd_dev.ep2drv));

        usbd_class_driver_t const* driver = get_driver(_usbd_dev.ep2drv[ep_num][ep_dir]);

        if (TUSB_REQ_TYPE_STANDARD != p_request->bmRequestType_bit.type) {
            // Forward class request to its driver
            TU_VERIFY(driver);
            return invoke_class_control(rhport, driver, p_request);
        } else {
            // Handle STD request to endpoint
            switch (p_request->bRequest) {
            case TUSB_REQ_GET_STATUS: {
                uint16_t status = usbd_edpt_stalled(rhport, ep_addr) ? 0x0001 : 0x0000;
                tud_control_xfer(rhport, p_request, &status, 2);
            } break;

            case TUSB_REQ_CLEAR_FEATURE:
            case TUSB_REQ_SET_FEATURE: {
                if (TUSB_REQ_FEATURE_EDPT_HALT == p_request->wValue) {
                    if (TUSB_REQ_CLEAR_FEATURE == p_request->bRequest) {
                        usbd_edpt_clear_stall(rhport, ep_addr);
                    } else {
                        usbd_edpt_stall(rhport, ep_addr);
                    }
                }

                if (driver) {
                    // Some classes such as USBTMC needs to clear/re-init its buffer when receiving CLEAR_FEATURE request
                    // We will also forward std request targeted endpoint to class drivers as well

                    // STD request must always be ACKed regardless of driver returned value
                    // Also clear complete callback if driver set since it can also stall the request.
                    (void)invoke_class_control(rhport, driver, p_request);
                    usbd_control_set_complete_callback(NULL);

                    // skip ZLP status if driver already did that
                    if (!_usbd_dev.ep_status[0][TUSB_DIR_IN].busy)
                        tud_control_status(rhport, p_request);
                }
            } break;

            // Unknown/Unsupported request
            default:
                TU_BREAKPOINT();
                return false;
            }
        }
    } break;

    // Unknown recipient
    default:
        TU_BREAKPOINT();
        return false;
    }

    return true;
}

// Process Set Configure Request
// This function parse configuration descriptor & open drivers accordingly
static bool process_set_config(uint8_t rhport, uint8_t cfg_num)
{
    // index is cfg_num-1
    tusb_desc_configuration_t const* desc_cfg = (tusb_desc_configuration_t const*)tud_descriptor_configuration_cb(cfg_num - 1);
    TU_ASSERT(desc_cfg != NULL && desc_cfg->bDescriptorType == TUSB_DESC_CONFIGURATION);

    // Parse configuration descriptor
    _usbd_dev.remote_wakeup_support = (desc_cfg->bmAttributes & TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP) ? 1u : 0u;
    _usbd_dev.self_powered = (desc_cfg->bmAttributes & TUSB_DESC_CONFIG_ATT_SELF_POWERED) ? 1u : 0u;

    // Parse interface descriptor
    uint8_t const* p_desc = ((uint8_t const*)desc_cfg) + sizeof(tusb_desc_configuration_t);
    uint8_t const* desc_end = ((uint8_t const*)desc_cfg) + tu_le16toh(desc_cfg->wTotalLength);

    while (p_desc < desc_end) {
        uint8_t assoc_itf_count = 1;

        // Class will always starts with Interface Association (if any) and then Interface descriptor
        if (TUSB_DESC_INTERFACE_ASSOCIATION == tu_desc_type(p_desc)) {
            tusb_desc_interface_assoc_t const* desc_iad = (tusb_desc_interface_assoc_t const*)p_desc;
            assoc_itf_count = desc_iad->bInterfaceCount;

            p_desc = tu_desc_next(p_desc); // next to Interface

            // IAD's first interface number and class should match with opened interface
            // TU_ASSERT(desc_iad->bFirstInterface == desc_itf->bInterfaceNumber &&
            //          desc_iad->bFunctionClass  == desc_itf->bInterfaceClass);
        }

        TU_ASSERT(TUSB_DESC_INTERFACE == tu_desc_type(p_desc));
        tusb_desc_interface_t const* desc_itf = (tusb_desc_interface_t const*)p_desc;

        // Find driver for this interface
        uint16_t const remaining_len = (uint16_t)(desc_end - p_desc);
        uint8_t drv_id;
        for (drv_id = 0; drv_id < TOTAL_DRIVER_COUNT; drv_id++) {
            // 打开驱动
            usbd_class_driver_t const* driver = get_driver(drv_id);
            TU_ASSERT(driver);
            uint16_t const drv_len = driver->open(rhport, desc_itf, remaining_len);

            if ((sizeof(tusb_desc_interface_t) <= drv_len) && (drv_len <= remaining_len)) {
                // Open successfully
                TU_LOG(USBD_DBG, "  %s opened\r\n", driver->name);

                // Some drivers use 2 or more interfaces but may not have IAD e.g MIDI (always) or
                // BTH (even CDC) with class in device descriptor (single interface)
                if (assoc_itf_count == 1) {
#if CFG_TUD_CDC
                    if (driver->open == cdcd_open)
                        assoc_itf_count = 2;
#endif

#if CFG_TUD_MIDI
                    if (driver->open == midid_open)
                        assoc_itf_count = 2;
#endif

#if CFG_TUD_BTH && CFG_TUD_BTH_ISO_ALT_COUNT
                    if (driver->open == btd_open)
                        assoc_itf_count = 2;
#endif
                }

                // bind (associated) interfaces to found driver
                for (uint8_t i = 0; i < assoc_itf_count; i++) {
                    uint8_t const itf_num = desc_itf->bInterfaceNumber + i;

                    // Interface number must not be used already
                    TU_ASSERT(DRVID_INVALID == _usbd_dev.itf2drv[itf_num]);
                    _usbd_dev.itf2drv[itf_num] = drv_id;
                }

                // bind all endpoints to found driver
                tu_edpt_bind_driver(_usbd_dev.ep2drv, desc_itf, drv_len, drv_id);

                // next Interface
                p_desc += drv_len;

                break; // exit driver find loop
            }
        }

        // Failed if there is no supported drivers
        TU_ASSERT(drv_id < TOTAL_DRIVER_COUNT);
    }

    // invoke callback
    if (tud_mount_cb)
        tud_mount_cb();

    return true;
}

// return descriptor's buffer and update desc_len
static bool process_get_descriptor(uint8_t rhport, tusb_control_request_t const* p_request)
{
    tusb_desc_type_t const desc_type = (tusb_desc_type_t)tu_u16_high(p_request->wValue);
    uint8_t const desc_index = tu_u16_low(p_request->wValue);

    switch (desc_type) {
    case TUSB_DESC_DEVICE: {
        // 获取描述符
        TU_LOG(USBD_DBG, " Device\r\n");

        void* desc_device = (void*)(uintptr_t)tud_descriptor_device_cb();

        // Only response with exactly 1 Packet if: not addressed and host requested more data than device descriptor has.
        // This only happens with the very first get device descriptor and EP0 size = 8 or 16.
        if ((CFG_TUD_ENDPOINT0_SIZE < sizeof(tusb_desc_device_t)) && !_usbd_dev.addressed && ((tusb_control_request_t const*)p_request)->wLength > sizeof(tusb_desc_device_t)) {
            // Hack here: we modify the request length to prevent usbd_control response with zlp
            // since we are responding with 1 packet & less data than wLength.
            tusb_control_request_t mod_request = *p_request;
            mod_request.wLength = CFG_TUD_ENDPOINT0_SIZE;
            // 这里返回端点0的大小
            return tud_control_xfer(rhport, &mod_request, desc_device, CFG_TUD_ENDPOINT0_SIZE);
        } else {
            // 返回所有描述符大小
            return tud_control_xfer(rhport, p_request, desc_device, sizeof(tusb_desc_device_t));
        }
    }
        // break; // unreachable

    case TUSB_DESC_BOS: {
        TU_LOG(USBD_DBG, " BOS\r\n");

        // requested by host if USB > 2.0 ( i.e 2.1 or 3.x )
        if (!tud_descriptor_bos_cb)
            return false;

        uintptr_t desc_bos = (uintptr_t)tud_descriptor_bos_cb();
        TU_ASSERT(desc_bos);

        // Use offsetof to avoid pointer to the odd/misaligned address
        uint16_t const total_len = tu_le16toh(tu_unaligned_read16((const void*)(desc_bos + offsetof(tusb_desc_bos_t, wTotalLength))));

        return tud_control_xfer(rhport, p_request, (void*)desc_bos, total_len);
    }
        // break; // unreachable

    case TUSB_DESC_CONFIGURATION:
    case TUSB_DESC_OTHER_SPEED_CONFIG: {
        // 配置描述符
        uintptr_t desc_config;

        if (desc_type == TUSB_DESC_CONFIGURATION) {
            TU_LOG(USBD_DBG, " Configuration[%u]\r\n", desc_index);
            desc_config = (uintptr_t)tud_descriptor_configuration_cb(desc_index);

        } else {
            // Host only request this after getting Device Qualifier descriptor
            TU_LOG(USBD_DBG, " Other Speed Configuration\r\n");
            TU_VERIFY(tud_descriptor_other_speed_configuration_cb);
            desc_config = (uintptr_t)tud_descriptor_other_speed_configuration_cb(desc_index);
        }

        TU_ASSERT(desc_config);

        // Use offsetof to avoid pointer to the odd/misaligned address
        uint16_t const total_len = tu_le16toh(tu_unaligned_read16((const void*)(desc_config + offsetof(tusb_desc_configuration_t, wTotalLength))));

        return tud_control_xfer(rhport, p_request, (void*)desc_config, total_len);
    }
        // break; // unreachable

    case TUSB_DESC_STRING: {
        // 字符串描述符
        TU_LOG(USBD_DBG, " String[%u]\r\n", desc_index);

        // String Descriptor always uses the desc set from user
        uint8_t const* desc_str = (uint8_t const*)tud_descriptor_string_cb(desc_index, tu_le16toh(p_request->wIndex));
        TU_VERIFY(desc_str);

        // first byte of descriptor is its size
        return tud_control_xfer(rhport, p_request, (void*)(uintptr_t)desc_str, tu_desc_len(desc_str));
    }
        // break; // unreachable

    case TUSB_DESC_DEVICE_QUALIFIER: {
        TU_LOG(USBD_DBG, " Device Qualifier\r\n");

        TU_VERIFY(tud_descriptor_device_qualifier_cb);

        uint8_t const* desc_qualifier = tud_descriptor_device_qualifier_cb();
        TU_VERIFY(desc_qualifier);

        // first byte of descriptor is its size
        return tud_control_xfer(rhport, p_request, (void*)(uintptr_t)desc_qualifier, tu_desc_len(desc_qualifier));
    }
        // break; // unreachable

    default:
        TU_LOG(USBD_DBG, "get desc_type error wValue=0x%x\r\n", desc_type);
        return false;
    }
}

//--------------------------------------------------------------------+
// DCD Event Handler
//--------------------------------------------------------------------+
TU_ATTR_FAST_FUNC void dcd_event_handler(dcd_event_t const* event, bool in_isr)
{
    switch (event->event_id) {
    case DCD_EVENT_UNPLUGGED:
        _usbd_dev.connected = 0;
        _usbd_dev.addressed = 0;
        _usbd_dev.cfg_num = 0;
        _usbd_dev.suspended = 0;
        osal_queue_send(_usbd_q, event, in_isr);
        break;

    case DCD_EVENT_SUSPEND:
        // NOTE: When plugging/unplugging device, the D+/D- state are unstable and
        // can accidentally meet the SUSPEND condition ( Bus Idle for 3ms ).
        // In addition, some MCUs such as SAMD or boards that haven no VBUS detection cannot distinguish
        // suspended vs disconnected. We will skip handling SUSPEND/RESUME event if not currently connected
        if (_usbd_dev.connected) {
            _usbd_dev.suspended = 1;
            osal_queue_send(_usbd_q, event, in_isr);
        }
        break;

    case DCD_EVENT_RESUME:
        // skip event if not connected (especially required for SAMD)
        if (_usbd_dev.connected) {
            _usbd_dev.suspended = 0;
            osal_queue_send(_usbd_q, event, in_isr);
        }
        break;

    case DCD_EVENT_SOF:
        // SOF driver handler in ISR context
        for (uint8_t i = 0; i < TOTAL_DRIVER_COUNT; i++) {
            usbd_class_driver_t const* driver = get_driver(i);
            if (driver && driver->sof) {
                driver->sof(event->rhport, event->sof.frame_count);
            }
        }

        // Some MCUs after running dcd_remote_wakeup() does not have way to detect the end of remote wakeup
        // which last 1-15 ms. DCD can use SOF as a clear indicator that bus is back to operational
        if (_usbd_dev.suspended) {
            _usbd_dev.suspended = 0;

            dcd_event_t const event_resume = { .rhport = event->rhport, .event_id = DCD_EVENT_RESUME };
            osal_queue_send(_usbd_q, &event_resume, in_isr);
        }

        // skip osal queue for SOF in usbd task
        break;

    default:
        osal_queue_send(_usbd_q, event, in_isr);
        break;
    }
}

//--------------------------------------------------------------------+
// USBD API For Class Driver
//--------------------------------------------------------------------+

void usbd_int_set(bool enabled)
{
    if (enabled) {
        dcd_int_enable(_usbd_rhport);
    } else {
        dcd_int_disable(_usbd_rhport);
    }
}

// Parse consecutive endpoint descriptors (IN & OUT)
bool usbd_open_edpt_pair(uint8_t rhport, uint8_t const* p_desc, uint8_t ep_count, uint8_t xfer_type, uint8_t* ep_out, uint8_t* ep_in)
{
    for (int i = 0; i < ep_count; i++) {
        tusb_desc_endpoint_t const* desc_ep = (tusb_desc_endpoint_t const*)p_desc;

        TU_ASSERT(TUSB_DESC_ENDPOINT == desc_ep->bDescriptorType && xfer_type == desc_ep->bmAttributes.xfer);
        TU_ASSERT(usbd_edpt_open(rhport, desc_ep));

        if (tu_edpt_dir(desc_ep->bEndpointAddress) == TUSB_DIR_IN) {
            (*ep_in) = desc_ep->bEndpointAddress;
        } else {
            (*ep_out) = desc_ep->bEndpointAddress;
        }

        p_desc = tu_desc_next(p_desc);
    }

    return true;
}

// Helper to defer an isr function
void usbd_defer_func(osal_task_func_t func, void* param, bool in_isr)
{
    dcd_event_t event = {
        .rhport = 0,
        .event_id = USBD_EVENT_FUNC_CALL,
    };

    event.func_call.func = func;
    event.func_call.param = param;

    dcd_event_handler(&event, in_isr);
}

//--------------------------------------------------------------------+
// USBD Endpoint API
//--------------------------------------------------------------------+

bool usbd_edpt_open(uint8_t rhport, tusb_desc_endpoint_t const* desc_ep)
{
    rhport = _usbd_rhport;

    TU_ASSERT(tu_edpt_number(desc_ep->bEndpointAddress) < CFG_TUD_ENDPPOINT_MAX);
    TU_ASSERT(tu_edpt_validate(desc_ep, (tusb_speed_t)_usbd_dev.speed));

    return dcd_edpt_open(rhport, desc_ep);
}

bool usbd_edpt_claim(uint8_t rhport, uint8_t ep_addr)
{
    (void)rhport;

    // TODO add this check later, also make sure we don't starve an out endpoint while suspending
    // TU_VERIFY(tud_ready());

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);
    tu_edpt_state_t* ep_state = &_usbd_dev.ep_status[epnum][dir];

#if TUSB_OPT_MUTEX
    return tu_edpt_claim(ep_state, _usbd_mutex);
#else
    return tu_edpt_claim(ep_state, NULL);
#endif
}

bool usbd_edpt_release(uint8_t rhport, uint8_t ep_addr)
{
    (void)rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);
    tu_edpt_state_t* ep_state = &_usbd_dev.ep_status[epnum][dir];

#if TUSB_OPT_MUTEX
    return tu_edpt_release(ep_state, _usbd_mutex);
#else
    return tu_edpt_release(ep_state, NULL);
#endif
}

bool usbd_edpt_xfer(uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
{
    rhport = _usbd_rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    // TODO skip ready() check for now since enumeration also use this API
    // TU_VERIFY(tud_ready());

    TU_LOG(USBD_DBG, "  Queue EP %02X with %u bytes ...\r\n", ep_addr, total_bytes);

    // Attempt to transfer on a busy endpoint, sound like an race condition !
    TU_ASSERT(_usbd_dev.ep_status[epnum][dir].busy == 0);

    // Set busy first since the actual transfer can be complete before dcd_edpt_xfer()
    // could return and USBD task can preempt and clear the busy
    _usbd_dev.ep_status[epnum][dir].busy = true;

    if (dcd_edpt_xfer(rhport, ep_addr, buffer, total_bytes)) {
        return true;
    } else {
        // DCD error, mark endpoint as ready to allow next transfer
        _usbd_dev.ep_status[epnum][dir].busy = false;
        _usbd_dev.ep_status[epnum][dir].claimed = 0;
        TU_LOG(USBD_DBG, "FAILED\r\n");
        TU_BREAKPOINT();
        return false;
    }
}

// The number of bytes has to be given explicitly to allow more flexible control of how many
// bytes should be written and second to keep the return value free to give back a boolean
// success message. If total_bytes is too big, the FIFO will copy only what is available
// into the USB buffer!
bool usbd_edpt_xfer_fifo(uint8_t rhport, uint8_t ep_addr, tu_fifo_t* ff, uint16_t total_bytes)
{
    rhport = _usbd_rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    TU_LOG(USBD_DBG, "  Queue ISO EP %02X with %u bytes ... ", ep_addr, total_bytes);

    // Attempt to transfer on a busy endpoint, sound like an race condition !
    TU_ASSERT(_usbd_dev.ep_status[epnum][dir].busy == 0);

    // Set busy first since the actual transfer can be complete before dcd_edpt_xfer() could return
    // and usbd task can preempt and clear the busy
    _usbd_dev.ep_status[epnum][dir].busy = true;

    if (dcd_edpt_xfer_fifo(rhport, ep_addr, ff, total_bytes)) {
        TU_LOG(USBD_DBG, "OK\r\n");
        return true;
    } else {
        // DCD error, mark endpoint as ready to allow next transfer
        _usbd_dev.ep_status[epnum][dir].busy = false;
        _usbd_dev.ep_status[epnum][dir].claimed = 0;
        TU_LOG(USBD_DBG, "failed\r\n");
        TU_BREAKPOINT();
        return false;
    }
}

bool usbd_edpt_busy(uint8_t rhport, uint8_t ep_addr)
{
    (void)rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    return _usbd_dev.ep_status[epnum][dir].busy;
}

void usbd_edpt_stall(uint8_t rhport, uint8_t ep_addr)
{
    rhport = _usbd_rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    // only stalled if currently cleared
    if (!_usbd_dev.ep_status[epnum][dir].stalled) {
        TU_LOG(USBD_DBG, "    Stall EP %02X\r\n", ep_addr);
        dcd_edpt_stall(rhport, ep_addr);
        _usbd_dev.ep_status[epnum][dir].stalled = true;
        _usbd_dev.ep_status[epnum][dir].busy = true;
    }
}

void usbd_edpt_clear_stall(uint8_t rhport, uint8_t ep_addr)
{
    rhport = _usbd_rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    // only clear if currently stalled
    if (_usbd_dev.ep_status[epnum][dir].stalled) {
        TU_LOG(USBD_DBG, "    Clear Stall EP %02X\r\n", ep_addr);
        dcd_edpt_clear_stall(rhport, ep_addr);
        _usbd_dev.ep_status[epnum][dir].stalled = false;
        _usbd_dev.ep_status[epnum][dir].busy = false;
    }
}

bool usbd_edpt_stalled(uint8_t rhport, uint8_t ep_addr)
{
    (void)rhport;

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    return _usbd_dev.ep_status[epnum][dir].stalled;
}

/**
 * usbd_edpt_close will disable an endpoint.
 *
 * In progress transfers on this EP may be delivered after this call.
 *
 */
void usbd_edpt_close(uint8_t rhport, uint8_t ep_addr)
{
    rhport = _usbd_rhport;

    TU_ASSERT(dcd_edpt_close, /**/);
    TU_LOG(USBD_DBG, "  CLOSING Endpoint: 0x%02X\r\n", ep_addr);

    uint8_t const epnum = tu_edpt_number(ep_addr);
    uint8_t const dir = tu_edpt_dir(ep_addr);

    dcd_edpt_close(rhport, ep_addr);
    _usbd_dev.ep_status[epnum][dir].stalled = false;
    _usbd_dev.ep_status[epnum][dir].busy = false;
    _usbd_dev.ep_status[epnum][dir].claimed = false;

    return;
}

void usbd_sof_enable(uint8_t rhport, bool en)
{
    rhport = _usbd_rhport;

    // TODO: Check needed if all drivers including the user sof_cb does not need an active SOF ISR any more.
    // Only if all drivers switched off SOF calls the SOF interrupt may be disabled
    dcd_sof_enable(rhport, en);
}

#endif
